A conventional 3GPP (3rd Generation Partnership Project) mobile communication system is configured to classify mobile stations into access classes (ACs) and to notify the mobile stations of an access class targeted for calling process restriction by use of notification information.
The mobile communication system is configured to periodically shift the target of calling process restriction from one access class to another so as to implement access restriction (group restriction).
For example, consider a case where 30% access restriction is started as shown in FIG. 1. In this case, such a mobile communication system determines access classes #4 to #6 among access classes #0 to #9 as the target of calling process restriction during a first Tsec in a cell to be a target of calling process restriction. The mobile communication system then notifies mobile stations located in the cell by use of notification information.
Then, after the completion of the first Tsec, the mobile communication system determines access classes #7 to #9 among the access classes #0 to #9 as the target of calling process restriction during a second Tsec in the cell to be the target of calling process restriction. The mobile communication system then notifies mobile stations located in the cell by use of notification information.
Meanwhile, in the 3GPP mobile communication system, a network for CS (Circuit Switch) and a network for PS (Packet Switch) are separated from each other. ACS domain is used to provide communication services such as a voice communication, a Videophone, and a UDI, while a PS domain is used to provide communication services such as a packet communication.
Here, the mobile communication system is configured to notify mobile stations of restriction rate for each domain by use of notification information so as to implement access restriction (group restriction) for each domain.
However, the conventional mobile communication system which implements the above-described access restriction has a problem that notification information has to be updated periodically to notify of the start and release of the calling process restriction.
Specifically, when updating the notification information periodically, the conventional mobile communication system has a problem that paging signals for notifying the notification information have to be transmitted to mobile stations frequently, and thus a radio section is occupied by the paging signals.
Furthermore, the conventional mobile communication system has a problem of an increase in battery consumption of a mobile station since the mobile station needs to receive the paging signals and check the notification information every time the notification information is periodically updated.
Meanwhile, in a LTE (Long Term Evolution) mobile communication system, since all the communication services are provided by use of a PS domain, access restriction needs to be performed independently for each communication service.
Therefore, when access restriction is performed independently for each communication service, such a LTE mobile communication system has a problem that a very large number of restriction rates (the number of access classes×the number of communication services, at maximum) are to be notified by use of notification information.